giúp mik vs mik đang cần gấp cảm ơn

Đúng ghi Đ, sai ghi S: a) 2,4 giờ = 2 giờ 40 phút b) 1,6 phút = 1 phút 36 giây c) 3 giờ 12 phút = 3,2 giờ d) 2 giờ 42 phút = 2,6 giờ

hiện tượng phản xạ toàn phần xảy ra ở đâu và như thế nào trong sợi quang

Tính cách thuận tiện nhất ạ : A,12347+23455+76545 B,123x4x25 C,2x4x25x50 D,(450x27):50 Ai tl đc e vote 5* ạ

x4 – (2 + cân(3) )x2 + 2cân3 = 0 thanks

Giúp ạ 1. The students in this class, ______ are from the provinces, are having trouble finding decent accommodation. a. most of whom b. many of them c. some of who d. all who 2. You have to be aware of the damage humans are doing to quicken the ______ of wildlife. a. extinct b. extinctive c. extinction d. extinctions 3. Cameron, ______ directed ‘The Titanic’, is one of the leading faces in Hollywood. a. that b. whose c. whom d. who 4. The population of the earth is increasing at a tremendous rate and ______ out of control. a. it will be b. soon will be c. have become d. are soon going to 5. The teacher gave some suggestions on what could come out for the examination a. effects b. symptoms c. hints d. demonstrations 6. While southern California is densely populated, ______ live in the northern part of the state. a. a number people b. many people c. few people d. a few of people 7. Mohandas K. Gandhi, ______ Mahatma, lived a noble life of fasting and poverty in order to work for peace and independence. a. that was called b. was called c. called d. calling 8. Your failure is the consequence of not studying hard enough for the test. a. cause b. motive c. result d. status 9. She ______ to study more English before enrolling at the university. a. was recommended b. recommended c. has recommended d. recommends 10. The teacher asked those who ______ their tests ______ in their papers. a. completed/ turn b. completed/ turned c. had completed/ to turn d. completed/ turns 11. Historian Barbara Tuchman was the first woman ______ president of the Academy of Arts and Sciences. a. whose election as b. to elect c. was elected d. to be elected 12. There are believed ______ over 300 species of trees in EI Yunque rain forest in Puerto Rico. a. to be b. being c. they are d. there are 13. Rarely ______ last longer than an hour. a. do tornados b. tornados c. tornados that d. tornados do 14. ______ for the fact that he was working abroad, he would willingly have helped with the project. . a. If it had been b. If it hadn't been c. Had it been d. Hadn't it been 15. New words are constantly being invented ______ new objects and concepts. a. to describe b. a description of c. they describe d. describe 16. A home computer ______ an opportunity for convenient and efficient work at home. a. provides b. to be providing c. which provides d. providing it

một nghiệm của phương trình 2x^2-(k-1)x-3+k=0 là:

7+65+98+6332++959+969+95/956*8+5876895+8

Giúp mình vs ạ mik cần rất gấp lun ạ Mình cảm ơn nhìu

Ba năm trước tuổi mẹ gấp 5 lần tuổi con, hiện nay tuổi mẹ gấp 4 lần tuổi con. Tính tổng số tuổi hai mẹ con hiện nay